Saving Titanic isn't just a documentary, but a fully scripted and acted movie told from the perspective of the coal shovelers and engineers who stayed in the bowels of the ship to keep the pumps and lights on. The movie is nicely edited with points where a narrator explains certain things that the crewmen themselves wouldn't be able to know at the time. (Like a further hull breech that wasn't visible because it was in a coal bunker, between boiler rooms)